Chemokines are polypeptidic leukocytic migration factors having molecular weights of about 10,000, and at least 21 types of peptide families having similar structures have been found. Further, at least 7 types of the chemokine receptors to which chemokines bind exist on leukocyte, and the receptors are considered to play an important role by means of selective migration and activation of leukocyte in many inflammatory diseases [Trends in Pharmacological Sciences, 17, 209-213 (1996)].
Accordingly, substances which specifically inhibit binding of chemokines to the chemokine receptors are considered to suppress the selective migration and activation of leukocyte and thus be useful as pharmaceutical drugs for prevention or treatment of e.g. acute or chronic inflammatory diseases such as septicemia, pneumonia, arthritis or allergic diseases, cancer, ischemic reflow disorder, arteriosclerosis, or rejection symptoms after organ transplantation operation.
Further, in recent years, the chemokine receptors have been identified to be receptors on target cells, which are important for AIDS virus (HIV) to infect to the target cells [Nature, 381, 661-666 (1996); Nature, 381, 667-673 (1996); Cell, 85, 1149-1158 (1996)]. Further, it was clarified that chemokines and chemokines which lack an amino acid residue on the amino terminal inhibit infection of HIV to the target cells [Science, 270, 1811-1815 (1995); Nature, 383, 400 (1996)].
Accordingly, substances which specifically inhibit functions of the chemokine receptors are considered to inhibit infection of HIV to the target cells and thus be useful as pharmaceutical drugs for prevention or treatment of acquired immune deficiency syndrome.